Recoil mechanism



Jan. 3, 1961 J. TANNENBAUM RECOIL MECHANISM 5 Sheets-Sheet 2 Filed May 2, 1957 JNVENToR. JnsephTannenbaun-L 5 Sheets-Sheet I5 mi W 0^ T RECOIL MECHANISM J. TANNENBAUM l Lw Jan. 3, 1961 Filed May 2, 1957 Jan. 3, 1961 J. TANNENBAUM 2,966,829

REcon. MEcHANIsM Filed May 2, 1957 5 Sheets-Sheet 4 86 ITE' E- 84 INVENTOR Jus Eph Tannenbaum J. TANNENBAUM RECOIL MECHANISM Jan. 3, 1961 5 Sheets-Sheet 5 Filed May 2, 1957 .5m QH INVENTOA mm www Nm Joseph Tannenbaum 1.7/ NN La E m s'A BY JOXDM ad. @WM- +711 @MQW NA @m United States Patent-l RECOIL MECHANISM Joseph Tannenbaum, Detroit, Mich., assignor to the United States of America as represented by the Secretary of the Army Filed May 2, 1957, Ser. No. 656,732

7 Claims. (Cl. 89-43) (Granted under Title 35, U.S. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.

The invention relates to recoil mechanism for ordnance and especially relates to mechanisms which employ uids to absorb and redistribute the recoil forces.

In the manufacture of armored tanks and selfpropelled gun vehicles space restrictions are very important as the limited space available must be used most eiciently. As the operating mechanism of the gun is located within the interior of the tank or other vehicle, the size of these mechanisms must be kept to a minimum, yet must be strong enough to withstand the large recoil forces produced when the gun is fired. The invention contemplates a'most efficient use of space to house the recoil mechanism, yet meet the necessary strength requirements.

' In prior gun recoil mechanism it has been common to integrate the recoil, counter recoil, and often the counter recoil buffering mechanism into a single fluid unit. This construction is susceptible to mechanical faiure upon air leaking into the uid system in that the air will affect all three stages of the recoil. Also, the use of an integrated recoil system necessitates a complete dismantl ng of the entire mechanism if the structure of any one of the three stages needs repair or a replacement of parts. The invention contemplates a design in which the iluid systems of the recoil, counter recoil and counter recoil buffering mechanisms are separate and a failure in one stage will not alfect the other stages, likewise one stage may be disassembled for repair without disturbing the mechanism of the other recoil stages.

It is therefore an object of the invention to produce a recoil mechanism which is compact and conforms closely to the contours of the gun breeching mecha nism thereby occupying a minimum of space.

Another object of the invention is to design a recoil mechanism that is light weight and of asimple construction.

kA further object of the invention is to construct a recoil mechanism in which the recoil, counter recoil and counter recoil buffering units are fluid operated, each unit-having an individual oil reserve and capable of being serviced independently.

Yet another object of the invention is to design a gun recoil mechanism in which the recoil, counter recoil and counter recoil buffering units are distinct mechanisms and may be spacially arranged at the discretion of the gun designer.

Fig. 1 is a cross-sectional elevation of one embodiment of the invention.

Fig. 2 is an end view of the Fig. l from the right.

Fig. 3 is a cross-sectional elevation of the counter recoil assembly.

Fig. 4 is a cross-sectional elevation of the buffering assembly.

' Fig. 5 is a cross-sectional elevation of another embodiment of the invention.

2,966,829 Patented Jan. 3,

Fig. 6 is an end view from the right of a gun breech incorporating the embodiment of Fig. 5.

Fig. 7 is a fragmentary cross sectional elevation View taken along the line 7-7 of Fig. 2 of the embodiment of the invention shown in Fig. 1.

As shown in Fig. 1, an embodiment of the invention comprises a gun 10 generally consisting of a barrel 12 supported by a cradle 14. A breech ring 16 is attached to the barrel 12 such that when the gun is fired the barrel 12 and breech ring 16 will move backward under recoil, guided by cradle 14. Concentric with the barrel 12 and lattached to the breech ring 16 is a recoil piston 18. Recoil piston 18 therefore will slide within cradle 14 and is supported by bearing 20 and bearing surface 22 of the cradle 14. An annular llange 24 is formed on the exterior surface of piston 18 and extends into a tapered cylinder 26 of the cradle 14. A oating seal 28 is slidingly interposed between the wall of cylinder 26 and recoil piston 18 and prevents the hydraulic uid which fills cylinder 26 from escaping. It will be noted that the flange 24 does not touch the wall of cylinder 26 but leaves a clearance whereby during recoil the uid may flow over flange 24 as the ange and piston 18 move rearwardly. The cylinder 26 is tapered converging towards the breech ring thereby increasing the resistance of the fluid flow over ange 24 as the piston 18 moves during recoil. As bearings 20 and 22 support the weight of the piston 18 and barrel 12, seal 28 will not be subjected to any appreciable weight and will provide an effective seal for a long period of time.

A reservoir 30 may be connected to cylinder 26 by means of conduit 32 and passageway 33 to supplement' any lost fluid.

As the gun 10 moves back to battery position, the fluid again ows to the rear of flange 24 and is ready to absorb the shock of the next recoil.

The gun 10 is moved back to the battery position by the counter recoil mechanism which consists of cylinders 34 fixed by bolts or such to the cradle 14. A piston 35 and piston rod 36 operate within cylinders 34, the outer end of which is connected to extension 38 of breech ring 16. It will be seen therefore that as the gun recoils,

extension 38 will move piston rod 36 rearwardly tending to compress the liuid in cylinders 34.

A recuperator 40 is bolted to the cradle as seen in Fig. 1. The recuperator consists of a cylinder housing 42, the ends of which are sealed by means of caps 44. A piston 50 is slidably positioned in housing 42 and is biased in one direction by means of springs 46. A conduit 49 connects the rear of cylinder 34 with opening 48 in the housing 42 permitting hydraulic fluid to ow from the cylinders 34 to the housing 42 when the breech ring 16, extension 38 and piston rod 36 move rearwardly during recoil. During this compression stroke, the liuid will force piston 50 into housing 42 compressing springs 46 and means are provided to bring the gun to rest inthe battery position with a minimum of shock.

The counter recoil buffering means comprises cylinders 54 which are fixed to the cradle 14 by bolts or such.

A piston rod 56 recprocates within cylinder 54 on which is attached a piston 58. The diameter of piston 58 is' slightly less than the internal diameter of cylinder 54 allowing the fluid in cylinder 54 to slowly flow from, A spring 60 biases` one side of piston 58 to the other.

aseiegsae'f' the. piston.. 58 and. piston. ring 16.

As the gun and breech ring 16 move back into battery, theabutment end 62- of piston-rod. 56 which is normally in abutting; relation withf breech ring'z16priorrto firing ofv thegumwill. contact the breech. ring 16, andthe resistance .of thefluid' flow from one, side of piston` 58 to the other will cushion the return movement;

The operation of the device is as follows:

As the gunrecoils, thev rearward movement of; the breech ring 16 moves. recoil piston. 18 to the right asl viewed in Fig. 1. Hydraulic fluid within tapered cylinder 26- ows over ange 24 with increasing resistance thereby absorbing .the recoil movement... As. the breech ring 16 movesrearwardly, thepiston 35and piston rods 360i the counter recoil cylinders 34 will also bemovinginthe samev directionithe'rebycirculating the fluid in cylinders-,Mthrough conduit149 and opening 48 tocompress Springs-46.`, After'thevrecoillmovement is completed, the uid pressure created by springs 46 returns the gun to battery through forcesk exertedin cylinders 34. Prior to the; gun reaching .battery position, the breech ring'. 16 will engage the abutment 62 ofthe counter recoil bufferpiston rod: 56 thereby" cushioning the return movement ofthe gun 10.

It: will be. observed that each of the unitsV is self-y contained and each has its own uid reservoir, therefore a failure of the counter recoil mechanism, for instance, willnot atfectthe recoil components or vice versa.

vShould oneof the units need repair or adjustment, there is no need to disturb the other units, as each may be serviced independently, whichv permits rapid repairl as is desired under battle conditions.. l

,A modicationrecoil mechanism is 'shown inA FigiVA 5 whereinY cylinders 64 are lixed to the cradle'14' by suitable means. As a pluraity of similar cylinders -64 are used, only onevwill be described, wherein vbreech ring 1.6 supportsa piston 66:l which is ofa tubular conguration and mounts a flange 68 at the end; The' internal wa'll o f'cylinder 64is tapered toward breech ring 16' and- .-hydraulic-liuid.llsthe space between piston 66 andv the wall of cylinder 64 such that during recoil the VpistonA 66 will be pulled rearwardly by the breechl ring 16 and thecowof Huid over liange 68 will cushion the recoil movement as described in the above embodiment.

At cylinder 70 is-supported at oneendby 'cylinder 64 and is concentric thereto. A cap 72 seals the above mentioned` end of cylinder 70 and provides the supporting means therefor.-

A piston 74 is also` mounted in breech ring 1'6, concentrictwith piston 66 andextends throu-gh the unsupported endof cylinder 70. A plunger 76 is formed on piston 74and an axial bore 78 intersects bore 80 forming a uid connection between the space defined by piston 74, the inner wall of cylinder 70` and chamber 82 'of the breechring 16'. v

A- pair of cylinders 84 are mounted'on the breech ring 16 for movement therewith. Cylinders 84 are in effect ainitrogen recuperator and consists of a floating piston 86A and an end plug-,88 which encoses a chamber 98 which is filled with a compressible gas such as nitrogen.

Chambers 82 are connected to each other by means of conduit 92 formed in the breech ring 16 and a conduit 94 provides a huid connection from one of the chambers 82 to the cylinder 84 and piston 86.

Counter recoil buffering cylinders 54, such as disclosed in the first embodiment, may be used with this modification and operate in the above described manner.

The operation is as follows:

During recoil, the flow of fluid over iiange 68 absorbs the recoil force as the breech ring 16 moves rearwardly. During this movement, piston 74 will also be drawn to the rear forcing the uid within cylinder 70 into bores 80'and 78. This causes fluid to be transferred through chambers 82 tothe cylinder 84 forcing piston 86 to c0111- rod. 56l toward the. breech..

press. the. gas. in chamber. 90. At theend of the..recoil motion the gas pressure will cause the fluid ow to reverse and return the gun 10 to battery. The counter recoil buffer cylinders 54 will absorb the kinetic energy created in the return movement.

This embodiment of recoil? mechanism may be readily adapted to a large varietyof guns.v- Any number of recoil cylinders 64/ or gas cylinders 84' may be used depending on` thev requirements. Buiier cylinders; 54.flike-. wise-may be located at the designers discretion formost elfective use. Here again it will be noted thatthe recoil, counter recoil and buffer units each have a separate liuid system, therefore eliminating a compounding of malfunction should airget intov the iiuid or leakage occur as would be the case in those systems. where a single fluid system is used to operate all of the recoil mechanism units or components.

It is therefore seen that the present invention discloses a`` recoil mechanism' which is compact, lightweight; dependable Aand may be arranged spaciall'y at theV discretionk of the designer. Repairs'and adjustments" may berrradel quickly to one unit without' disturbing .other units, and a failure of one phase of the recoil mech anism will'not alect the performancek ofthe other phases; I.

Although thev inventionV has'been' particularlylshown and described in two modifications, it will be understood that the invention is capable of further modification. and that changes in the construction may be made without departing from the spirit or scope of the invention as ex-y pressed in the following claims.

1'. GunV barrel recoil movement responsive4 mechanismforabsorbing b-arrel recoil and for returning saidbarrel" to batteryf'position on a gun with'a finedT cradle and' a.

movable barrel with breechring slidably mountedin said cradle; said mechanism comprising, lin corribi'nation, a` barrel recoil movement absorbing fluidsystem' includingVv a'recoil cylinderformed within said vcradle concentricwitli said barrel, a movablev tubular recoil piston in andcon-v centric with said* recoil cylinder and attached to said" breech ring' for recoil andv counter recoilactuated move# ment-therewith, a barrel ange on said recoil piston ex'- tending into and ofv a diameter` less than said'recoil kcyl-y inder to permit restricted iiuid ow'therein, anda recoil force absorbing fluid within said recoil cylinder, a barrel counter recoil movement providing iluid system tiuidl'yvr independent of said' barrel recoil movement absorbing'` uid system and including a counter recoil cylinder fixed-f to said cradle, a movable counter recoil piston within said counter recoil cylinder andactuatably' attach'edto said breech ring for actuatingl counter recoil movementv of said breech ring upon termination of barrelr recoil movel ment, said counter recoil piston movably cooperating with saidtbarrellrecoil pistonk during barrel recoil to absorb barrel lrecoil forces, arecuperator having a recuperator cylinder xed to said cradle and in fluid communicationwith saidl counter recoil cylinder, a recuperator piston vand. compression means in said recuperator cylinder com-v pressively responsive to uid pressure of said counter recoil cylinder for actuating' counter recoil movement'o; said counter recoil piston, said recuperator piston movably cooperating with said recoil and counter recoil pistons duringbarrel recoil to absorb barrel recoil forces, and'a iiuid barrel counter recoil movement bulfering sys tern fluidly independent ofsaid barrel recoil movementV absorbing and counter recoil movement providinguid systems, said buffering' system including a buiieriiuid cylinder attached, to said cradle, buffer fluid in. said cyll' inder, a movable buffer piston Within said buiiercylinder and having a movable piston rodin conta-ct with and movably responsive` tov recoil and counter recoily movement of said breech'ring, said buffer piston movably cooperating during barrel counter recoil movement with said recoil piston to cushion said counter recoil .move-v ment of said barrel, said buffer piston having a restricted" uid how-permitting diameter less than the internal diameter of said buler uid cylinder.

2. Gun recoil movement responsive mechanism as set forth in claim 1 in which said recoil movement absorbing uid system includes a oating uid seal slidingly interposed between said recoil cylinder and recoil piston.

3. Gun recoil movement responsive mechanism as set forth in claim 1 wherein said compression means in said recuperator comprises a plurality of compression springs.

4. Gun recoil movement responsive mechanism as set forth in claim 1 wherein said recoil cylinder is tapered converging toward said breech ring.

5. Gun barrel recoil movement responsive mechanism for absorbing barrel recoil and for returning said barrel to battery position on a gun with a fixed cradle and a movable barrel with breech ring slidably mounted in said cradle, said mechanism comprising, in combination, a barrel recoil movement absorbing fluid system including a recoil cylinder carried by said cradle adjacent said barrel, a movable tubular recoil piston concentrically within said recoil cylinder and attached to said breech ring for recoil and counter recoil actuated movement therewith, a flange on said recoil piston in and of a diameter less than said recoil cylinder to permit restricted lluid ow therein, and a recoil force absorbing uid within said recoil cylinder, a barrel counter recoil movement providing uid system uidly independent of said barrel recoil movement absorbing fluid system and including a counter recoil cylinder iixed to said cradle, a movable counter recoil piston concentrically within said counter recoil cylinder and xed to a piston rod secured to said breech ring for actuating counter recoil movement of said breech ring upon termination of barrel recoil movement, said counter recoil piston movably cooperating with said barrel recoil piston during barrel recoil to absorb barrel recoil forces, a recuperator cylinder xedly mounted to said cradle and adjacent to and in fluid communication with said counter recoil cylinder, a recuperator piston and compression means within said recuperator cylinder for actuating counter recoil movement of said counter recoil piston upon termina tion of barrel recoil movement, and counter recoil fluid within said counter recoil cylinder responsive to reco-il movement of said counter recoil piston to compress said compression means, said recuperator piston movably cooperating with said recoil and counter recoil pistons during barrel recoil to absorb barrel recoil forces, and a tluid barrel counter recoil movement buiering system lluidly independent of said barrel recoil movement absorbing and counter recoil movement providing uid systems, said buffering system including a buffer uid cylinder fixed to said cradle, a movable buffer piston within said buffer cylinder, and a piston rod on said buffer piston in contact with and movably responsive to recoil and counter recoil movement of said breech ring, said buffer piston movably cooperating during barrel recoil movement with said recoil piston to cushion said counter recoil movement of said barrel.

6. Gun recoil movement responsive mechanism as set forth in claim 5, wherein said recoil cylinder is tapered converging toward said breech ring.

7. Gun recoil movement respon-sive mechanism as set forth in claim 5, wherein said compression means within said recuperator cylinder comprises a gas.

References Cited in the ile of this patent UNITED STATES PATENTS 1,227,161 Lehmann et al. May 22, 1917 1,480,557 Joyce lan. 15, 1924 1,607,350 Joyce Nov. 16, 1926 2,072,099 Davison Mar. 2, 1937 2,358,340 Lucht Sept. 19, 1944 2,715,856 Kramer et al. Aug. 23, 1955 FOREIGN PATENTS 1,132,801 France Nov. 5, 1956 

